While it may not seem unusual to have sex on your wedding anniversary, some couples are now choosing to celebrate the occasion by having sex with professional photographers capturing it all on camera.

Constance Faulk and Eric Vogel are successful photographers who have turned to the lucrative area of “personalized porn.” Clients pay the husband and wife team as much as $4,000 to have them take pictures of them having sex. For the couples featured in this "Nightline" piece, the fee was waived for letting "Nightline" film.

“Constance is very fine art oriented, and I kind of expressed an interest in wanting to shoot something sexy,” Vogel told ABC News' "Nightline." "And she challenged me to shoot something that is kind of frequently depicted literally and do it in a way that’s kind of respectful and more artistic."

As people continue to look for ways to spice up their relationships, business is booming for Faulk and Vogel. More and more couples are becoming interested in memorializing their moments of intimacy.

“As far as the type of people ... there are born-again Christians, people who you would completely expect to do this, with tattoos,” Vogel said.

“Then we have people who’ve had cancer and are recovering from that, and that’s always beautiful,” Faulk said.

A client couple of Faulk and Vogel's who asked “Nightline” not use their names said they don’t consider themselves exhibitionists but have no problem having sex in front of strangers.

“I think making it a business thing, a professional thing makes me a lot less nervous,” the woman told “Nightline.” “We are excited that they are excited to do this, that we can find people like that.”

Faulk and Vogel insisted their work is not pornography.

“Nowadays, we photograph everything. You know, there [are] whole Instagram accounts dedicated to what you had for lunch ... the important things,” Vogel said. “This is one of those big important things.”

But Logan Levkoff, Ph.D., a self-described sexologist and the author of a new book, “Got Teens? The Doctor Mom’s Guide to Sexuality, Social Media and Other Adolescent Realities,” told “Nightline” that people should be concerned about over-sharing.

“I’m not sure how many people in our own lives want to be that involved in our personal, intimate lives,” Levkoff said.

However, people can now not only share their private moments, but also cash in on them on websites such as MakeLoveNotPorn.com.

Husband and wife "Violet" and "Ry" both have day jobs, but also like to upload videos of themselves having real sex on the website.

“We got a lot of people coming to the blog and commenting and interacting with us, saying, like, ‘This is the kind of that we’re looking for. We love this,’” Violet told “Nightline.” “It just felt instantly like ... there are tons of other people like us out there looking for something that they can’t find.”

While the website’s founder, Cindy Gallop, said she wants to socialize sex and make it as shareable as anything currently posted on social media, others think this may not be a great idea.

“Part of the challenge these days, living in this high-tech, digital world, is that what is ours often and very quickly becomes something that is not ours,” Levkoff said. “So before you do anything that can be public, I just ask that couples consider how they are going to manage the outcomes if the outcomes are much different than their expectations.”

Faulk and Vogel said their clients are comfortable with the risks. While their subjects are making love, the photographers are making art. The Museum of Sex is about to include one of Faulk and Vogel’s portraits in its permanent collection. The photo hangs alongside a Picasso piece.

“It feels like that people like it, and we’re going to have a larger audience see it,” Faulk said. “And it makes me feel more respectable, too. I can’t wait to see what it looks like hanging up on a wall.”

“We are trying to do something positive and bring a positive message out," Vogel said. "It will make it open for everybody, and I think people find that interesting."

“Plus, it’s just social," Faulk added. "The social conversation regarding sexuality is a lot more open now.”